Answer:
v = 4 m/s
Step-by-step explanation:
Given data:
Mass of elevator = 500 kg
Energy = 4000 j
Velocity = ?
Solution:
1/2 mv² = 4000 j
1/2 (500 kg)v² = 4000 j
v² = 4000 j×2 / 500 kg
v² = 4000 kg. m²/s² ×2 / 500 kg
v² = 8000 kg. m²/s² / 500 kg
j = kg. m²/s²
v² = 16 m²/s²
v = 4 m/s